With rapid progress of technology to fabricate high-integration semiconductor devices in recent years, circuit wiring patterns or interconnections have been becoming increasingly small and fine, and devices fabricated as integrated circuits have also been further downsized. Under these circumstances, there is a need for a process of planarizing a surface of a substrate, e.g. a semiconductor wafer, by polishing away a film formed on a substrate surface. As a manner for this planarization, polishing using a chemical/mechanical polishing (CMP) apparatus has heretofore been performed. This kind of chemical/mechanical polishing (CMP) apparatus has a turntable with a polishing cloth (pad) bonded thereto and a top ring. A substrate to be polished is interposed between the turntable and the top ring. In this state, the top ring and the turntable rotate while the top ring is pressing the substrate against the polishing cloth (pad) on the turntable with a predetermined pressure. In addition, a polishing solution (slurry) is supplied to an area of sliding contact between the substrate and the polishing cloth (pad), thereby polishing a surface of the substrate to a flat and specular surface.
Meanwhile, research has been conducted on a process of polishing semiconductor wafers and the like using a polishing tool including a fixed abrasive, in which abrasive particles, e.g. cerium oxide (CeO2), are fixed together by using a binder, e.g. a phenolic resin. In polishing using such a polishing tool, because a polishing surface of the tool is rigid unlike that used in conventional chemical/mechanical polishing, projections on an uneven surface are preferentially polished away, but depressions are difficult to polish away. Accordingly, it is easy to obtain absolute flatness advantageously. In addition, a self-stop function is available, depending on composition of components of the polishing tool, whereby when projections have been completely polished away to form a flat surface, a polishing rate reduces remarkably, so that polishing will not virtually proceed any longer. Furthermore, because a polishing process employing such a polishing tool does not use a polishing slurry containing a large amount of abrasive particles, a load imposed in terms of environmental issues reduces favorably.